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From: Tudor Ambarus <tudor.ambarus@linaro.org>
To: broonie@kernel.org,
	andi.shyti@kernel.org,
	semen.protsenko@linaro.org
Cc: krzysztof.kozlowski@linaro.org,
	alim.akhtar@samsung.com,
	linux-spi@vger.kernel.org,
	linux-samsung-soc@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	andre.draszik@linaro.org,
	peter.griffin@linaro.org,
	kernel-team@android.com,
	willmcvicker@google.com,
	Tudor Ambarus <tudor.ambarus@linaro.org>
Subject: [PATCH v4 03/16] spi: s3c64xx: avoid possible negative array index
Date: Mon,  5 Feb 2024 12:45:00 +0000
Message-ID: <20240205124513.447875-4-tudor.ambarus@linaro.org>
In-Reply-To: <20240205124513.447875-1-tudor.ambarus@linaro.org>
References: <20240205124513.447875-1-tudor.ambarus@linaro.org>
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The platform id is used as an index into the fifo_lvl_mask array.
Platforms can come with a negative device ID, PLATFORM_DEVID_NONE (-1),
thus we risked a negative array index. Catch such cases and fail to
probe.

Fixes: 2b90807549e5 ("spi: s3c64xx: add device tree support")
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 2b5bb7604526..c3176a510643 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -1189,6 +1189,9 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
 					     "Failed to get alias id\n");
 		sdd->port_id = ret;
 	} else {
+		if (pdev->id < 0)
+			return dev_err_probe(&pdev->dev, -EINVAL,
+					     "Negative platform ID is not allowed\n");
 		sdd->port_id = pdev->id;
 	}
 
-- 
2.43.0.594.gd9cf4e227d-goog